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Finding the Fourth Proportional to 631.47, 870.52 and 421.57

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Solution

The fourth proportional to 631.47, 870.52 and 421.57 is: 581.16

Step by Step Solution

  1. Step 1: Write the proportion equation
    631.47 : 870.52 = 421.57 : x
  2. Step 2: Convert to fraction form
    631.47/870.52 = 421.57/x
  3. Step 3: Cross multiply
    631.47x = 870.52 × 421.57
  4. Step 4: Simplify right side
    631.47x = 366,985.12
  5. Step 5: Solve for x
    x = 366,985.12/631.47
  6. Step 6: Final answer
    x = 581.16

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Why These Related Problems?

These problems maintain the same ratio (1.38) or explore similar proportional relationships. Practicing with related ratios helps build understanding of proportional relationships.